


Brother mine

by BlushLouise



Series: Small packages [2]
Category: Transformers - All Media Types
Genre: Fluff and Smut, Holoforms (Transformers), M/M, Plot What Plot/Porn Without Plot, Smut, Spark Sexual Interfacing, Transformers Plug and Play Sexual Interfacing, doing it in holoform
Language: English
Status: Completed
Published: 2018-03-12
Updated: 2018-03-12
Packaged: 2019-03-30 13:00:08
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,176
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13952082
Author URL: https://archiveofourown.org/users/BlushLouise/pseuds/BlushLouise
Summary: Sunstreaker's back from a stay in the brig. Sideswipe is welcoming.'Nuff said.





	Brother mine

**Author's Note:**

> So this is my first time writing human(ish) M/M, plug'n'play and spark merges. Let me know how I did, won't you?

The door opens, and Sideswipe lifts his head.

“Hey. You’re out.”

Sunstreaker just nods. His finish is dull, dusty. “Hey.”

Sideswipe climbs off the berth, walks over to his brother slowly. Takes his hand. “I missed you, bro.”

Sunstreaker grunts. Thankfully, Sideswipe is fluent in ‘Sunstreaker’, and this particular sound means ‘missed you too, you glitch’.

So Sideswipe kisses him. That’s what you do, right?

It doesn’t take much more than that to light them up. It never has.

“Berth,” Sunstreaker moans, pressing against his brother, fingers caressing sensor horns and delving into sensitive transformation seams.

“Nuh-uh, you’re too dusty,” Sideswipe protests breathily. “I’d say wash racks, but I don’t think I can wait that long.” He drags his denta down Sunstreaker’s golden head fin, drawing out a moan. “Holoform?”

“Holoform,” Sunstreaker agrees, tilting his head to give Sideswipe better access to his neck. “Your hood.”

“Love you,” Sideswipe groans, letting his fingers dance across Sunstreaker’s port covers before stepping back. They transform in sync, and Sideswipe’s hands are back on Sunstreaker’s smooth skin before his twin is even fully solid.

He’s not sure at this point what he actually prefers. The charge, mind-to-mind contact and hot touches of their root mode, or the damp, sticky, soft physical heat of the holoform. He presses his teeth into Sunstreaker’s shoulder in little nibbles, angry red marks marring the pale holoform skin.

Sunstreaker’s beautiful, arching into the bite and moaning. He pushes Sideswipe backwards until Sides is lying back against his own hood. The strange double sensation of holoform and plating is distracting at first, but he embraces it.

“Sunny,” he gasps, as his twin’s mouth moves down his throat, his tongue tasting its way to Sides’ chest.

“Love you,” Sunstreaker growls, and the wave of lust and adoration shot over the bond almost overloads Sideswipe then and there.

He whines, letting the rest of his clothing disappear and lifting his legs to catch Sunny’s hips. “Want you,” he mewls, hips lifting against his brother, his throbbing hot human flesh aching for attention.

Sunstreaker doesn’t disappoint. With a possessive snarl and a sharp hold of Sideswipe’s hips, he slams home in one easy, practised motion. Sideswipe’s holoform flesh, programmed to fit his brother perfectly, clenches around Sunstreaker’s girth.

“Oooooh yes,” Sideswipe breathes, “more, please, Sunny –“

“Mine,” Sunstreaker purrs, repeating the motion.

Sideswipe keens. “Yours,” he agrees, drowning in his brother. “Yours, oh Primus, Sunny!”

Sunstreaker is relentless, hands and lips roaming over Sideswipe’s holomatter skin, pace never faltering. Sideswipe’s lips are always moving, voicing a never-ending stream of curses and praise and ohPrimusohplease _there_ s. As Sunstreaker bites down hard on his neck, marking Sideswipe as his, Sideswipe comes with a howl, ejaculating all over both of their stomachs. The noise and the smell and the tight, slick heat pushes Sunstreaker over, and he roars his completion into Sideswipe’s neck.

“Sunny,” Sideswipe breathes after a few minutes of catching his breath. “Primus, Sunny, I’ve missed you.”

Sunstreaker lifts his head, looks into his eyes. Then their lips meet again, greedily, possessively, and Sideswipe can feel his holoform responding as Sunstreaker deepens the kiss. He realizes then that Sunstreaker never pulled out – he’s still buried to the hilt in Sideswipe’s clenching heat, and Primus, it feels amazing.

Sideswipe doesn’t protest when his brother begins moving again, hips thrusting gently and tongue exploring Sideswipe’s mouth. He lifts his hands up, touching, caressing, and then Sunstreaker’s moaning into his mouth, a deep, wanton sound that makes Sides shiver. Sunstreaker encourages Sideswipe’s arms to encircle his neck, and taking hold of his brother’s hips lifts him up in one smooth motion.

“Want you over me,” he whispers, and Sideswipe keens, part in response to the words and part because Sunny’s hardened fully inside him and oh, this position, Sunny goes _deep_ , thrusting slightly with each step.

They collapse on the edge of the soft berth covers in a sweaty mess, connected to each other by mouths and hips. The bedding is thick, plush, and Sunstreaker rolls them until he’s lying on his back. Sideswipe breaks the kiss again and sits up, still impaled on his brother.

“Sunnyyyyy,” he moans, feeling that hot length inside him, trembling as he leans back.

“So hot,” Sunny croons, leaning up on his elbows and watching him with a smirk. “So fragging hot, Sides.”

Fingers move on him then, stroking from his knees up to his hips, skirting his hot shaft and tracing taut stomach muscles, nails gliding over his skin, up to circle sensitive nipples. Sideswipe is panting, head thrown back, rocking gently on top of his brother.

“Love you, Sideswipe,” Sunstreaker breathes. “Now move, fragger.”

Sideswipe has to grin at that, and he catches Sunstreaker’s hands in his own, using them as unneeded support. “So impatient,” he murmurs, smirking down at his gorgeous brother.

“Speak for yourself,” Sunstreaker growls, and Sideswipe leans in to kiss him by way of apology. Having Sunny in the brig for eight days had been hard on both of them.

Sunny turns his head into the kiss, which means he’s forgiven, and he sends a burst of love and affection over the bond as he rocks faster on Sunstreaker’s shaft. The golden twin grunts, then, breaking the kiss to bite at Sideswipe’s neck again, pulling his hands free and placing them on Sideswipe’s hips, thumbs caressing the sensitive skin across his pelvis. Sideswipe gasps and collapses against his brother.

Then he really begins moving.

“So good, Sunny, so fragging gorgeous,” he moans, hands clenching in Sunstreaker’s dark hair, and when Sunstreaker’s impatience takes over and he picks Sideswipe up physically to slam him down, going oh so deep and making Sideswipe arch and keen, Sideswipe lets him take control.

The pace hastens, their breathing speeds up, and Sideswipe has never seen anything quite so hot in his life as Sunstreaker’s cloudy eyes half-hidden under sweat-damp hair.

“Mine,” Sunstreaker growls again, pushing Sideswipe down hard, and Sideswipe comes for the second time, tipped over by the sheer look of lust in his brother’s gaze. Sunstreaker follows almost instantly; the golden twin comes loudly, intensely, thrusting a few times more into Sideswipe and _roaring_.

Sideswipe collapses against Sunstreaker’s hot, sweaty chest, clinging to him. After a moment, Sunstreaker huffs, putting his arms around him and twisting until they’re side by side, face to face.

Post-interface Sunstreaker cuddles. They’re one of Sideswipe’s absolute favorite things  – only beaten by interfacing with Sunstreaker. Sideswipe grins, leaning his forehead against his brother’s.

And Sunstreaker tolerates it. Sideswipe knows he’s not imagining the subtle pressure that means Sunstreaker’s leaning back.

For a moment, neither of them say anything. Sides relishes in the warmth and comfort that is his brother.

Then Sunstreaker smirks. “Too dusty, huh?”

Sideswipe grins. “Yeah. You’re covered in brig dust, bro.”

“Can’t have that.” Sunstreaker’s blue eyes glint, and Sideswipe can feel his brother’s amusement over the bond. He tries to hold on for a moment, but Sunstreaker pulls away gently but firmly. “I’m going to hit the wash racks.”

The golden twin stands, then, stretching and turning slightly, and Sideswipe knows he’s being treated to a rare sight. Sunny’s showing off. And Sides doesn’t mind. Not even when the dark-haired sexy holoform fades away, and Sunstreaker transforms to give him the same show in root mode. Sideswipe grins as he feels this body responding again, despite the fact that right now they’re not technically compatible.

Stretch done, Sunstreaker turns and heads for the wash rack door. He turns at the last minute, shooting Sideswipe a smirk. “You coming?”

Sideswipe grins. Frag yeah, he was coming. He lets the holoform fade away and stands to follow his brother.

 

Sunstreaker’s golden plating looks good wet, too. Sideswipe presses against him, taking care not to push hard enough to mar the perfect finish. That is, until Sunstreaker pulls him close with a snarl, grinding against him, mouth moving on his neck.

Okay. Sideswipe was totally up for that.

Black fingers moves on gold and silver plating, dragging across cabling, dipping in between plating to tease at hot protoform. Sideswipe’s mouth goes after Sunstreaker’s head fin again, with predatory intent, and his brother purrs.

Sideswipe is so fragging crazy about his brother, it’s not even funny. And as talented, perfect fingers tease at the gap between his pelvis and leg plating, Sideswipe abandons the head fin to latch onto Sunstreaker’s main neck cable, mouthing and licking.

“Berth,” Sunstreaker moans, for the second time tonight, and this time Sideswipe can’t find it in him to object. Not with those fingers pulling at his cabling. He merely lets Sunstreaker pull him along, dry them both quickly, and then entice him back to berth. It’s not hard.

When Sunstreaker moves in front of him, showing off the shine, the strength, the utter perfection that is his twin, Sideswipe follows.

They crash down on the berth proper this time, and Sideswipe pulls Sunstreaker close. “Want you,” he purrs, letting his fingers trace Sunstreaker’s beautiful frame.

Sunstreaker just growls. He turns with them, pulling loose, leans down to let his glossa trace down Sideswipe’s central transformation seam.

“Ah, frag, yes,” Sideswipe hisses. “Frag, Sunny, yes, yesyesye- PRIMUS!”

Sunstreaker smirks, pulls back slightly from the port cover he’s teased loose. “Want your cables.”

Like Sideswipe was going to argue with that. “Want yours.” Sunstreaker smiles at that, a tiny lift to the corners of his mouth, and Sideswipe melts. “Want you _now_.”

“Impatient,” Sunstreaker says, obviously enjoying turning the tables on his brother.

“Well, yeah,” Sideswipe replies cheekily. “I’m waiting for _you_. Anyone would be impatient to get some of that.”

“I’m not for just anyone,” Sunstreaker pouts, and Sideswipe purrs at him, pushing his lust and love over the bond.

“Oh, I know. You’re perfect, Sunny. So slagging hot, I can’t even say it.”

Sunstreaker looks at him then, and Sideswipe knows he’ll do anything for that look to be aimed at him again. And he knows he’s the only one it’ll be aimed at.

Sunstreaker connects their cables, and Sideswipe reels at the first tentative datapacket. Sunny feels strong and satisfied in the bond, but he clearly still needs reassurance.

The packet Sideswipe sends back is stronger, and he follows it with a heady pulse of _love/affection/want/mine_ across the bond.

Sunstreaker _snarls_ , hands tightening on Sideswipe’s frame possessively, mouth pressing against Sideswipe’s, and this time the datapacket comes fast, strong, and Sides is almost undone already.

Back and forth, back and forth, and when sparks begin jumping from Sunstreaker’s frame to his own, Sideswipe pauses.

“Sparks,” he gasps against his brother’s mouth. “Please Sunny, I want your spark –“

“ _Yes_ ,” Sunstreaker breathes, leaning back just enough that Sideswipe can see his chest plates cracking open. “Sides, yes, so good –“

Sideswipe opens his own chest plates, and then his brother collapses into him, mouths and chests meeting.

And Sideswipe ceases to exist. Sunstreaker ceases to exist. There’s just one, one full spark, both of them flowing seamlessly into each other, no borders or distance between them anymore.

The part that is Sideswipe can feel his other half’s _longing/loneliness/self-disgust/failure_ , the dark sensations that sometimes threatens to tear Sunstreaker apart. In return, the Sunstreaker half revels in the _love/adoration/faith/trust_ that is offered, letting it swamp their shared spark, letting it pull the two halves closer together until there’s nothing else there, just the two of them. Just the one of them.

 _I love you_ , they think together. _Mine/love/mine/family/trust/love_.

It seems endless, but it’s not. As they slowly begin to peal apart, spark splitting down a familiar line to form two entities again, Sideswipe gasps and holds onto his brother. He feels the loss deeply, the him/not-him that is Sunstreaker fading away slightly, and it makes him hold on tight to the yellow plating just as his brother holds on tight to him.

And then the pulsing of energy back and forth becomes too much, and still reeling from the merge Sideswipe overloads hard, hard enough to pull his brother with him, and with plating still crackling and chest plates still half unlocked he falls offline.

 

He onlines slowly, feeling warm, safe, loved. Without onlining his optics he know that his brother is close.

*Sunny?*

The clear presence that is Sunstreaker responds with amusement and familiar exasperation. No trace of the _lost/hurt/alone_ that had been there the last couple of days. *Don’t call me that.*

Sideswipe smiles, nuzzles into the warm plating he can now feel next to him. Strong arms curl around his shoulders, pulling him closer. *Whatever you say, sunshine of mine.*

“You’re such a glitch.” Sunstreaker sighs, a put-upon and exaggerated sound, and Sideswipe chuckles.

“Maybe,” Sideswipe replies softly, pressing even closer to his brother. “But I’m your glitch. And you love me for it.”

Sunstreaker huffs, but he doesn’t deny it. And Sideswipe’s almost swept away by the wave of _love/trust/adoration_ that comes over the bond.

*Yeah,* he replies. *Love you too, bro.*


End file.
